Duncan eobertson



geiten l tetes` @anni @frn DUNCAN ROBERTSON, 4OF- DETROIT., MICHIGAN.

.Letters PatengNo. I(4,003, dated Febrmizry 4, 1868; unter-lated 'December 12, 1867.

IMPRovED CENTRE-BOARD ros vessels.

To, WHoM 1r MAY concessi Be it known that I, DUNcAN ROBERTSON, ofDeti-olt, in the county of'Wayne, inthe State ofMichigan, have invented a new andimproved Method of Attaching Oentre-Boards tovessels; and I do'declar'e that the followt ing is an accurate description thereof, referencel lbeing had to tlrejnocorn panying drawings, and to the letters of reference marked thereon, constituting a part oi' this' specifications-'-H Figure 1 is a transverse sectional viewr` Figure 2 is a longitudinal sectional view.

The letters of reference are the same in both figures..

My invention is designed to dofaway with the ordinary centi-aboard used in vessels,

required, which takes up room in the hold ofthe vessel. l

I use aniron centre-board, A, attached to the keeloi' the vessel, B, b eye-bolts d ,ivhieh pass throughj the keel B. To the inner ends of the e D D, which pass up lthrough hollowl stanchions E E, to the deck oi" the vessel F, Wh'ere they are secured hy stops G. s i Y When it is required to use the centre-board A, by casting oft" the chains or ropes I-III, which are attached to the outer edgeiof the centre-board A at b, and pass up}through other hollow stanchions, I I, to the'decli of the vessel, where they arevattached to a winch, or any other proper method fori-'raising 'or lowering them, the

-centre-,boardA can be' hield in place, either perpendicularly or at-angy required angle.

` or chains H H.

centre-board drops by swinging'upon lthe journals C C.' Then, bytightening the chains or'ropes H H, the

When not in use, the centre-board A can. be foldedV against the bottom ofthe vessel by casting oil either ofthe chains or ropesvH H, and hauling taut upon the' other by means of the winch, or other Ineens used for 'raising or lowering the ropes To unship this centre-board, itis only necessary to cast ofi'. all the chaius'or vvropes D D and II H, (first attaching av buoy to one of thcm,) when -the centre-board A will sink, and can easily be recovered by means of the buoyed line or chain. y

I This centre-board can 4be attached to avessel while on the stoc way interfere with launching the vessel.

By the use of this keel I save the space in the vessel's hold usually taken up hy the well, and ani not obliged to cut away any part of the keel, and frame the side freine directly into the keel. I

What I clainras my invention, and desire to secure by Letters Patent, is- The combination and arrangement ofthe iron centre-board A, the or chains D D II I-I, the hollow stanchions E `E I I, and tlie purpose designed'.

ks, as, being` tlush with the keel, it can' in no the stops-.G G, arrangedsuhstantially as described for 'DUNCAN ROBERTSON.

Witnesses:

J. W. HOUGHTELIN, H. F. Enn'rs.

by'whieh t wen is y-in'eans of journals C G, Working in ye-bolts a a, I attach chains oiropes,

journals C C, the eye-bolts a a, the ropes-I 

